So far there have been used a great number of devices for the inspection and sorting of small objects, particularly fruits and small edible products, based on the transportation through endless means, such as bands, chains, or conveyor belts, of the fruits to be inspected, to a section in which their inspection is carried out. This inspection, as the case may be, can consist of different analysis, such as size, shape and existing defect analysis, or a sorting and separation of fruits based on size, shape, etc.
These devices for fruit inspection are for example the devices for the automatic sorting of agricultural products, such as fruits, with a roller conveyor, said rollers being tilted to distribute the products to different auxiliary paths and a measuring station.
Other devices are formed by a fruit and vegetable treatment and manipulation train, which also has a pre-selection conveyor which through the rollers derives the products to different stations. Another gauging conveyor rejects the units which are too big or too small.
These machines have the inconvenience that they do not carry out very detailed or precise selections, not detecting small shape variations or visually noticeable defects. In order to solve these problems, there exist nowadays sorting machines which by the use of cameras inspect small articles which are displaced on a conveyor belt, but which have the problem of offering a very limited number of product views, unless many cameras are installed to be able to obtain many views of the articles, increasing the inspection system costs as well as its mounting costs. It must also be considered that installing cameras under the machine to obtain lower views of the product produces a constant problem of dirt accumulating on said cameras. Particularly, certain systems make the products advance and rotate through rollers under a vision system, providing multiple views to the vision system. This system has a problem when the product to be inspected is very small because the holes between the rollers must be very small, and, either they do not allow an ejection of the products from the inside through said holes, or if they allow it, as the products are so small, the ejection of each one of them affects the products close by, displacing them or even ejecting products which should not be ejected. In order to avoid these problems, the ejection must be made from the outside, so it has to be made right when the products abandon the roller train, in the air, but this has the inconvenience that there is a problem of instability at the discharge due to the acceleration suffered by the products when they pass from one straight section of the conveyor to a curved one. This punctual acceleration leads to changes in the normal discharge path of the conveyor products, which prevents their precise ejection, as they are not in the estimated place at the estimated time.
It was therefore desirable a system which attained an efficient fruit and small product inspection and sorting, avoiding the inconveniences existing in the previous systems in the state of the art.